The Fart Injection Threshold (FIT) is the exact pressure necessary for a person's "hiney" which is properly and securely mated with a cloth surface (couch, car seat, pillow, etc.) to break through the somewhat permeable fabric with flatulence. If one cheek of said hiney is higher than the other or your pelvis is tilted, the fart will fail to penetrate the fabric barrier and thus pass through the choad channel and dust the back of your testies.
1. Last week I had to put plastic on my couch because some bad children broke into my house and fumigated my furniture. Good thing scientists have yet to discover how to break the Fart Injection Threshold of 3,000 Mil plastic.

2. Yo, my girlfriend has such a sexy butt, I used to always sniff her car seat. That was until her pops told me that he frequently breaks the Fart Injection Threshold of her car seat when he borrows her car to get Indian food!
by Dr.FartScientist May 4, 2017
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